With melanoma: You can never be too rich or too thin! But, you can be too young!!!

Definitions to keep in mind:
Thickness (Breslow) - actual thickest part of a slice of the tumor...remembering that the lesion can rise above the level of your skin.
Clark level - a description of how deeply the tumor penetrated the layers of your skin.

Thin melanoma and late recurrences:  it is never too thin and never too late.  Richetta, et al.  Med Oncol.  April 2014.

"In the absence of risk factors, thin melanomas [generally defined as 1mm or less] present a long-term survival; however recurrences may occur....Median disease free survival of the entire cohort [in this study] was 26 months and three patients developed late metastases. Nine patients developed extra-nodal metastases as first recurrence, while cases of positive sentinel lymph node biopsy were not found....No consensus exists as to which patients with thin melanomas are at risk for metastases or late recurrences."

Sentinel node biopsy improves prognostic stratification in patients with thin melanomas and an additional risk factor.  Mitteldorf, et al. Ann Surg Oncol.  March 2014.

"Sentinel lymph node biopsy for patients with thin melanomas is not generally recognized as a clinical standard...931 patients had sentinel lymph node biopsies.  210 had thin melanomas.  Of the 210...All..showed at least one of the following risk factors:  ulceration (4%), Clark level IV (44%), nodular growth pattern (11%), mitoses (59%), regression (38%) or age </= 40 years (27%)."

....observed surprisingly high SLN positivity rate of 18%.  [Most of the literature says that for thin, 1mm or less, melanoma lesions the rate of finding a positive node is less than or equal to 5%.  Now, while that may sound nice....that is one of twenty people!!!]  "There was a trend towards a higher SLN positivity rate in younger patients. Breslow, ulceration, mitoses, nodular growth pattern, and sex did not reach significance.  Regression was significantly more frequently found in very thin melanomas (</=0.75mm) and tended to be significant in this subgroup."

"SLNB improves prognostic stratification in patients with thin melanomas having an additional risk factor....Our data suggest that SLNB should be offered to patients with thin melanomas, if ulceration, nodular growth pattern, mitoses or regression are present, or if the patient is younger than 40 years of age."

Identifying high risk patients with thin (</=1mm) primary cutaneous melanomas.  Gimotty et al. ASCO 2013. 

"The prognostic factors used to identify patients with thin melanomas at high risk of regional nodal metastasis or melanoma specific death include:  thicker tumors (>/= 0.75mm), deeper levels of invasion (Clark level IV or V), ulceration and dermal mitosis....Study cohort = 42, 080 patients with only one primary and no clinical evidence of metastasis at the time of diagnosis....Five year melanoma specific death rates were not uniform in 100 tumor thickness groups, but were stable in each of the following ranges:  4.3% - 0.01-0.17mm, 1.3% for 0.18-0.66mm, 3.1% for 0.65-1.00mm.  Among all patients, ulceration and level were the strongest prognostic factors.  Thickness was a weaker prognostic factor.  Four risk groups for regional nodal metastasis risk were identified:  
1) level IV/V (11.8%), 
2) level II/III with nodular or acral lentiginous histologies (15.1%),
3) level III and 0.11-0.17mm and not nodular or lentiginous (9.3%),
4) level III and 0.01-0.02mm and not nodular or letiginous (6%).
...Stratification schemes comparable to this will inform decision making."

My story:  Well, you can never be too rich if you are sick, in need of care longer than 2 minutes, or have to travel for your care!!!  Clearly, being thin (as applied to melanoma lesions) is not terribly protective.  I try not to say too much on the forums as Janner attempts to lull people out of their terror after having been diagnosed with an "atypical lesion"....she's definitely correct there.  No great risk, people.  It is gone.  Watch your skin.  Move on.  But, with this "thin melanoma" business...things can get murky!  Trust me!!!  My initial stats:  2003.  On right upper back.  Breslow measurement = 0.6mm.  Clark level IV.  No ulceration.  1/mitosis/hpf(high power field).  Yet, I had one positive node with "micrometastasis, Starz classification 1" (per Dr. Starz of Germany himself).  Later, we had a report from Martin Mimh, MD of Harvard, who noted that, yes, my tumor was a Clark Level IV (there had been some confusion on the part of the local 2-wong-fu pathologist) and "as you would expect" in such a case, I had a "positive node".  Age at diagnosis - 39.

As the thickness of the lesion was less than that indicated for a SNB at the time, we pushed for it anyway.  I am certain I would not be here today had I not had it done.  Turns out now, I WAS in a high risk group, despite the thinness of the lesion.  I was less than 40 years of age with a Clark level IV lesion. 

I don't want to frighten folks with this information.  But, this is the data.  And I am LIVING proof.
Take care of yourself.  Discuss with your melanoma specialist!  Yours, c